1. Field
Embodiments relate to a secondary battery.
2. Description of the Related Art
A secondary battery is a battery that is chargeable and dischargeable, unlike a primary battery that is not chargeable. A secondary battery may be used as an energy source for, e.g., a mobile device, an electric vehicle, a hybrid vehicle, an electric bicycle, an uninterruptible power supply (UPS), etc. According to type of an external device for application, a secondary battery may be used as a single battery or a battery module in which a plurality of secondary batteries are electrically connected to one another as a single unit may be used.